An FBI agent gathers up crime scene tape while moving the news media further away from a field outside Detroit where agents are searching for the alleged remains of former Teamsters union president Jimmy Hoffa.

(CNN) - Just three miles from the house in which I grew up, FBI agents are digging for the body of Jimmy Hoffa. For two days they've been wading through waist-high grass in a field in Oakland Township, Michigan, trying to unearth secrets from one of the most famous cold cases in American history.

Hoffa was the leader of the Teamsters, the biggest union in the auto industry, in a time when the Big Three dominated the global car market. But his ties to the mob are believed to be what put him in peril.

He was last seen on July 30, 1975 leaving the Machus Red Fox restaurant in suburban Detroit. There have been a slew of tips over the past decade that have led to investigations. Floorboards were torn out of a home in a search for blood, a driveway was drilled for human DNA and most notably in 2006 a horse barn was torn down so FBI agents could dig beneath it.

All of these searches turned up nothing.

So, why are they digging again?

"What I tell people is, if that was your loved one, would you want the FBI and the law enforcement to be doing this? And I think most people would say yes."

Andy Arena is a former FBI Special Agent who was in charge of the FBI's Detroit office from 2007-2012. He says the FBI has two messages to send, one to criminals and one to law-abiding citizens: That the FBI never gives up.

Investigators tasked with this latest search are carrying binders that read "Big Dig 2" on the cover, a wink to that last hunt now viewed mostly as a punchline.

But Arena says this claim carries more weight than any before, because the 85-year-old former mobster who pointed authorities to this latest spot is from La Cosa Nostra in Detroit. Which, unlike the syndicates in other big cities, is made up of only family members, either by blood or by marriage. And who can keep a secret better than family?

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(CNN) – Today was a day of secrets revealed and secrets searched for. Here's what's waiting for you in today's News Day:

The NSA gives us a peek

We got a look under the nation's cloak of secrecy today. General Keith Alexander, head of the recently much-talked-about National Security Agency, appeared before a House committee today to answer questions about its surveillance programs . He didn't give up the whole hog, but he did serve up some bacon. Alexander said that more than 50 terror plots were thwarted by electronic surveillance.

Diplomatic trafficking in focus

It's a story that has had too many chapters. Today, we look at the world of diplomats who bring domestic workers to the US, and then treat them like slaves. CNN's Libby Lewis goes inside the world of diplomatic trafficking and meets one of the women who was held against her will.

Jimmy Hoffa is more difficult to find than Jimmy Hoffa

It's been a bad 38 years to be a field in Michigan. In 1975, former Teamsters kingpin Jimmy Hoffa disappeared outside a Detroit-area diner, kicking off an extremely persistent search. It seems that every year or two a new tip surfaces, causing investigators to dig up this field or under that barn. Now, a new "highly credible" tip about Hoffa's whereabouts has surfaced from alleged mobster Tony Zerilli, and a new round of Michigan field digging is underway.

Editor's Note: Listen to the full story in our player above, and join the conversation in our comments section below.

(CNN) – Pandora Radio is a pioneer in putting music online. Pandora allows people to pull up endless music on their computers and take it on the go with a smart phone.

So why are they investing in a small South Dakota radio?

The internet radio giant claims it is paying too much in music licensing fees from companies like ASCAP and BMI. Not only did Pandora file suite against ASCAP, the company bought KXMZ in South Dakota because of a loophole. Companies with terrestrial radio pay less in licensing fees.

[1:03] "Pandora's argument is that is that they shouldn't be penalized just because they are a stand alone internet radio service. They want the ASCAP fees that are available to stations that are a part of this radio music license committee settlement."

Editor's Note: Listen to the full story in our player above, and join the conversation in our comments section below.

(CNN) – First he forced chain restaurants to post calorie counts on their menus. Then he pushed forward with a ban on large size sugary soft drinks.

Now New York City Mayor Michael Bloomberg wants people to set aside their food scraps so they can be collected for composting.

"It gives people a way to participate in composting even if you don't want to go whole hog yourself," said Brooklyn Botanic Garden spokesperson Kate Blumm. "So you don't want worms under your sink? Fine. You don't want to have to go out to your backyard with a pitchfork once a week? Fine. This is a way that you can participate, or really I can participate, as well."